In recent years, prefabrication-type heliports made of aluminum have widely been used in place of those made of asphalt or concrete. The aluminum heliport is prefabricated, and therefore, it can be placed on a roof of a building, ground or the like more easily than an asphalt heliport or the like. Moreover, the aluminum heliport has advantages such that the structural strength of the building can be reduced and so on, due to the lightweight heliport. FIG. 20 and FIG. 21 are a whole structural drawing and a perspective assembly view, respectively, of a conventional heliport. A conventional heliport 100 employs a prefabrication style and is constructed using deck materials 110, beams 120 and cross beams 130. A plurality of the deck materials 110 are crossed over and bedded on the beams 120 to form a heliport surface H. The deck materials 110, 110 adjacent to each other are not joined directly to each other; each deck material is connected onto the beams 120 and fixed to the beam with bolts. A plurality of the beams 120 are crossed over the cross beams 130 to serve as the foundation of the deck materials 110. The cross beams 130 are constructed by crossing large-sized beams over columns that are provided on a flat ground or on a roof of a building, and serve as the foundation of the beams 120. No patent applications on the above conventional heliport 100, with respect to the problems to be solved described later, have been made in Japan. Therefore, the description of related patent literature is omitted.
Recently, demands have been made for a prefabricated heliport 100 that can be easily placed on water. For such a heliport, a structure is proposed, in which the deck materials 110 are bedded on a structure floating on water and that serves as the foundation (the drawing omitted). A few floating structures having sufficient strength and that can easily be set on water in case of emergency, are available. However, many of such floating structures are not rigid enough or are too brittle to serve as the foundation for a heliport. If the beams 120 are provided on such a floating structure and the deck materials 110 are bedded thereon, there is a problem in that a concentrated load and an impact load peculiar to heliport damages the floating structure.
The present invention has been carried out considering the above problems, and the objects of the present invention are to provide a heliport as well as a building and construction member that can be placed on a simple floating structure and have strength tolerable for a peculiar impact load and concentrated load.